Choosing to consider built form relative to unstable conditions requires a
recalibration of the metrics used to evaluate material performance in terms of
resolution, durability, and longevity. The work included here rejects the Vitruvian
virtue of firmitas, which has guided material practices toward firmness, durability
and strength for centuries. Instead it embraces more emergent processes such
as degradation, re-composition, accumulation, and growth. This shift from the
making of site assemblies that resist natural processes to the making of those
that anticipate and support them inspires the development of new materials
and construction methods. The 13 projects included here are first responders to
a call for Landscape Surfaces.

FX
SURFACE

Landscape Surfaces; such as paving assemblies, drainage structures, retaining
walls, and erosion control systems, occupy a potentially dynamic boundary
between the ground and human habitation. In this position they have the unique
capacity to simultaneously influence biologic process and sensory experience.
This report documents a series of prototypical Landscape Surfaces that embrace
this dual capacity toward the making of unique places through greater legibility
of landscape process and the coupling of social and biological agendas. Surface
FX are the combined performative effect and experiential affect of these
assemblies.

SURFACE FX 2013

Katherine Jenkins
Gwendolyn McGinn
and
Brian Osborn (eds.)

SURFACE

FX
Surface FX

Spring 2013

Landscape Architecture Department
School of Architecture
University of Virginia

Illustrated in the chart to the left, Zimmerman goes on to discuss a range of solutions to slope
stabilization based on slope. She recommends that slopes from 0% and up to 33% (1:3) require no
slope reinforcement. Slopes of 33% and up to 50% (1:2) can be maintained using plant material. She
notes that, “ the most natural protection against erosion for slopes is planting, i.e. using roots to secure
the soil. A combination of extensive and intensive roots has a positive effect, as for example when
using herbaceous plants and grasses, or the combination of shallow and deep roots when using woody
plants, as this makes it possible to achieve even rooting throughout the soil”. In addition to these
below surface advantages, plant material provides an uneven texture at grade, reducing the velocity of
water and sediment flowing over the surface.
For slopes of 45% and up to 66% (1:1.5) Zimmerman recommends the use of Erosion Control Mats.
She notes that, “the effectiveness of simple planting can be optimized by erosion protection mats.
Geotextiles are used, usually made of coconut, jute, straw or a combination of these materials. They
provide temporary protection for the soil covering until the vegetation has developed, and rot down
over the early years (jute 1-2 years, coconut 3-4 years)”.
10

Concave

Complex
(convex-concave)

< Deposition

Convex

Erosion >

Uniform

Distance >

Uniform
Concave
Convex
Complex (convex-concave)

Complex
(concave-convex)
While all of the strategies noted above are used regularly in practice today, they each take a utilitarian approach to slope stabilization and do not treat it as a place-making endeavor. With TECmat we
promote an integrated approach to slope stabilization, utilizing plant material, biodegradable matting,
mineral soil additives, and micro-topographic adjustment. In doing so we produce a single surface, capable of stabilizing slopes, restoring natural resources, and managing storm waters, while also creating
aesthetically satisfying forms that create memorable places for human habitation.

2.0 Micro-topography
In Soil Erosion: Processes, Prediction, Measurement, and Control, Terrance Toy, et al, discuss the primary factors influencing soil erosion. Among these they include topography. Topography, they explain,
“refers to the geometry of the land surface. The important geometric variables are slope length and
steepness, shape in the profile view, and shape in the plan view.” Illustrated in figure 2.1 are common
slope shapes in the profile view. Figure 2.2 plots anticipated erosion and deposition relative to profile
shape. To highlight two distinct examples, Uniform slopes begin to erode material away from the
surface. This erosion continues to increase indefinitely as slope length increases. A Complex (convexconcave) slope shape, alternatively, will erode material over the convex portion of the shape, then
deposit that material over the concave portion. Within the complex shape, erosion and deposition are
nearly equal. This Complex slope shape is comparable to what Zimmerman refers to as a “terrace”.
11

The TECmat is shaped to produce a terracing effect on the existing grade at a micro-scale. That is,
instead of producing a single terrace on the hillside, TECmat produces a series of periodic terraces,
each equalizing erosion and deposition within itself. This micro-topographic change is illustrated
through a series of iterative sectional views (figures 2.8-2.12) and in plan (2.3-2.7). Our team conducted
preliminary field-testing to see if a biodegradable material could influence slope shape if secured to
the slope for a period of time. The results of this test are visible in figures 2.12 and 2.13. A paper egg
carton was secured to a slope and was monitored for 75 days. The photograph taken on day 1 shows
the egg carton sitting above the surface of the existing grade. The photograph taken on day 75 shows
a significant portion of the egg carton covered in sediment and the grade beginning to contour around
the carton material.

3.0 Material
Paper as a Substrate
When thickened, paper can act as a substrate to mediate between the ground and
the forces that might degrade it. In time, paper will decompose and become a part of
the ground, but during this process it can perform a variety of functions.

Figure 3.1
Plant material positioned on
plane of slope where it is least affected by topographic changes.

The rigidity of the paper can physically hold and shape the ground as microtopographic conditions are formed. Paper can also perform as a substrate that assists in
the establishment of plants. In time the plants that the paper initially supported will
provide the primary support in stabilizing the groundplane. By that point, the paper
itself will have degraded and become a part of the soil.
As a substrate, thick paper is quite absorbent. The paper that we created for our prototype absorbs about 200mL of water per square foot. This will immediately improve
the ability of a highly compacted site to absorb water. Tests of egg cartons demonstrated that the paper substrate maintains moisture longer then the soil.

Figure 3.2
Base of plant is buried by deposition.

Stratification
Many woodland plants can be difficult to start from seed. A stratification process is
required to break the seeds from dormancy. Often moist and cold temperatures are
required for 30 to 60 days. In commercial horticultural settings, paper is often the
substrate used during seed stratification because paper maintains an even moisture
level which assists in the stratification.
For our prototype, we chose to embed Schizachyrium scoparium and Oxydendrum
arboreum seeds into the paper. According to Lee Eddleman, Schizachyrium scoparium has a germination rate of 85-98% at optimum temperature, but 30 to 60 days of
stratification are required to break the seeds dormancy before it can germinate (214).
When installed in the fall, the TECmat will provide structural support to the soil as the

Figure 3.3
Base of plant is exposed by erosion.

embedded seeds achieve their stratification requirements. By spring, the TECmat will
have degraded slightly to allow the roots to penetrate.

rock. This rock, mostly granite, explains the
presence of monadnocks, which are isolated hills

During the development of the TECmat, we

of resistant rock that rise above the peneplain

considered Observatory Hill to be the site of

(Office of the Architect 9).

our eventual installation. There are many areas
on Observatory Hill that would be appropriate

The university is located in a cluster of these

protect through aesthetic engagement and

monadnocks. The intricate ridges of these local

the structural support of the TECmat. In Figure

granite landforms in combination with the

4.2, three sites are demarcated at Hereford

visibility of the distant Blue Ridge Mountains

Residential College on Observatory Hill. Site 1 is a

creates a sense of identity for the university.

lightly wooded area adjacent to dormitories and

In addition to this embedded sense of place,

north of a community garden. It could be a site

the university was carefully situated within two

of woodland restoration and would engage the

watersheds. The headwaters of Mooreâ&#x20AC;&#x2122;s Creek

garden. Site 2 is the site of the prototype. It is a

and Meadow Creek are located at Observatory

steep embankment located beside a parking lot.

Hill. Although Observatory Hill had not been

To the north is a forest dominated by chestnut

developed until recently, it has been a part of the

oaks; the site marks a line between the remaining

campus since itâ&#x20AC;&#x2122;s inception. The ownership of

forest and the developing campus. Site 3 is

Observatory Hill would secure a source of water

beside the Vaughn House. It is located between

for the university during its consistent expansion.

the disturbed site of the dormitories and Lodge
Creek, which feeds Mooreâ&#x20AC;&#x2122;s Creek.

As the university expanded, these tributaries
and streams were encroached upon and
degraded. Large portions are now buried
underground in culverts and popes.
23

24

6.0 Plant Communities
The site chosen for our installation is on a southern facing slope
of Observatory Hill. Itâ&#x20AC;&#x2122;s soil is thin and acidic and supports an

Figure 6.1
Schizachyrium
scoparium

oak-heath forest dominated by Quercus montana. The canopy also
includes Liriodendron tulipifera, Pinus virginiana, and Nyssa sylvatica. Ericaceous plants, including Kalmia latifolia and Gaylussacia
baccata form a light understory.
Although not present on Observatory Hill, Oxydendrum arboreum
is often an overstory associate in developed oak-heath forests
(USDA, NRCS). Seeds for Oxydendrum arboreum were embedded in
the TECmat as a way to introduce this associate into the edge of the
forest on Observatory Hill. Sourwood can be difficult to establish in
a nursery setting. By planting seeds during a restoration process,

Figure 6.2
Oxydendrum
arboreum

the establishment of Oxydendrum arboreum is not required for successful erosion control, but any successful germination would add
an additional aesthetic richness to the forest edge.
Amerlanchier arborea is also often embedded in the understory
of an oak-heath forest. It is currently planted at the edge, and we
propose that there could be places within the TECmat for transplanting established trees and shrubs. This would increase the transition from the meadow condition (introduced by Schizachyrium
scoparium) to an enclosed forest. The Schizachyrium scoparium
would quickly stabilize the soil with their deep root system, but by
introducing a shrub layer, shade will eventually make it difficult for
the grass to grow, and more forest plants can begin to emerge from
the shifting meadow condition.
By introducing associate species and considering the effects
through a sequence of plants, the slope can be stabilized by a
diversity of plant root typologies.

25

Figure 6.3
Amerlanchier
arborea

7.0 Restoration of
Natural Features
Figure 7.1
Initial Installation

The TECmat, embedded with
Schizachyrium scoparium and
Oxydendrum arboreum seeds
is installed on site in late fall
with one to two inch caliper
amelanchier arborea planted at
the crowns of the paper mat.

26

Figure 7.2
3 Months

The Schizachyrium scoparium seeds have germinated and begin to break through the TecMat creating a sparsely grassy slope. The TECmat catches
runoff and eroded soil from the slope above.

Figure 7.3
15 Months

The Schizachyrium scoparium reaches 3 feet in
its second season of growth stablilizing the slope
with its 3 to 6 foot roots. The TECmat begins to
degrade but continues to shape the soil beneath
it creating small terraces.

The Amelanchier arborea reach a height of 12
feet and, together with the growing Oxydendrum
arboreum, shade out the grasses on the slope.
The TECmat has fully degraded and becomes
incorporated into the soil on site.

28

Figure 7.6
15 years

The Amelanchier arborea reach
maturation. The Oxydendrum
arboreum grow to 20 feet
extending the canopy of the
existing adjascent forest over
the sloped site. Some subtle
terracing remains and erosion
is significantly reduced by the
density of tree roots. The once
barren and eroded slope has
been twransformed into an
extension of native forest and a
thriving ecosystem.

29

Figure 8.1
Molds for the paper form are
milled from Low-density polyethylene (LDPE) plastic using a CNC
router.

Figure 8.2
The molds
consist of one
layer of woven
steel mesh
between two
layers of LDPE.
Figure 8.3
The molds are
secured with
nylon leveling
mounts which
also allow excess water to
drain from the
paper pulp.
Figure 8.4
The four completed molds
used in the
first prototype.

30

8.0 Prototyping & Implementation
The first TECmat prototype was fabricated and installed at Site
2 at Hereford Residential College (see section 3). The intention
of the prototype was to verify the anticipated micro-topographic
change to the existing grade as a result of the TECmat, as well as
to test the ability of the Little Blue Stem seed to germinate and
establish itself on the hillside. The prototype was installed on
Thursday, November 29, 2012. At the time that this document
was produced, no significant results were available to report. Our
team continues to observe and record changes to the prototype.
Our team also continues to refine the design and form of TECmat,
as well as investigate additional appropriate materials for use in
future installations. Specifically, we have been experimenting with
wool felt, and are interested in its ability to hold water and plant
nutruents while also being fastened to maintain shapes ideal for
micro-topographic manipulation.
The prototype covers approximately 12 square feet of hillside.
The total cost to produce the prototype was approximately $300.
This amount includes the materials used to produce the molds,
which can be resused, reducing the cost of future prototypes and
installations.

Figure 8.5
A custom paper pulp is made
using recylced paper from the
Architecture Schoolâ&#x20AC;&#x2122;s waste bins.
Figure 8.6
The paper pulp is poured over the
mold. Little blue stem seeds are
hand set into the pulp.
Figure 8.7
When dry, the paper panels are
removed from the molds.

31

Figure 8.8
The completed
TECmat is
secured to the
existing grade
with 5/8â&#x20AC;?x12â&#x20AC;?
steel landscape spikes.

Figure 8.9
Mounting
holes are
designed into
the TECmat
paper molds
to recieve the
landscape
spikes.

32

Figure 8.10
The first TECmat prototype
consists of 12
panels, each
approximately
9â&#x20AC;?x36â&#x20AC;? across
the diagonals.

Local Water Infrastructure Built and Managed by Communities
The people living within the rural communities in the Limpopo Region construct and manage (with
their hands and human scale tools) much of their own infrastructure. This design proposal utilizes
skills that the people of this region already have, enabling them to construct and manage their own
water resources. Instead of relying on the municipal government to supply these rural towns with
water, this infrastructure becomes the responsibility of the town. This not only removes water as a
tool for political control, but also creates and even more symbiotic relationship between citizens and
the ecological processes that surround them, therefore making citizens inherently aware of seasonal
ecological processes.
The proposed local infrastructure is produced through a series of faceted surface changes that
dependent on operation and program. The facets change in slope, material and relationship to ground
depending of the operation of collection, horizontal or vertical movement.

Figure 9
Diagrammatic model showing ground infiltration in plan. The field of constructed facets prevents erosion in the rainy season,
and slows water enough to allow ground infiltration. This increases ground water supply, therefore supplying water for the local
reservoirs down slope. In addition, the soil acts as a filter for the reservoir supply.
49

display the retention and infiltration of site runoff
structure a new typology of land formation that

Project Background

allows for moist centers, filtration buffers, dry

Grids are a universally employed spatial arrange-

circulation paths, and water features that are

ment and organizational tool. The manipulation

engaging and linked.

of a grid provides contrasts between one set of
organizing principles and another. It produces
exciting shapes and spaces. In this project, grids
are pinched in strategic areas to achieve greater
porosity of the grid. When used to create a
surface, letting a draped surface sag over these
larger pores in the grid achieves having areas
that are deeper and therefore can hold mroe
water or fill in times of flood.
59

Early studies simply questioned how a grid could
be manipulated. Using grasshopper, a simple grid
geometry was arranged and then pinched around
particular points in the plane. The tension of these
grids and their attraction to those points was varied
to produce different effects.

60

A rope grid was constructed to conceive of the grid
as a manipulated landscape. This allowed for the
testing of surface tension and configuration. Where
the grid remains stable and even, the surface is
taught and stable. Where it pinches, stable taught
circulation paths are formed with open sagging
areas around them, providing a potential wetland
configuration.

61

Before applying the grids on a site-scale, the grids were first imagine as tiles that
could link up along a path. To achieve this, agrid was created with a cross through
the center, which achieves endpoints at the edges which can be connected no matter how the grid is manipulated or rotated. The cross was bent to create different
circulation paths, then divided in to a varied number of points with various tolerances
for attracting the grid.
62

63

Unique tiles can be rotated and linked up to create different strategies for areas with
varying levels of saturation. The coloration of the tiles on the following page highlights their arrangement.
64

65

The grid pinching scheme, once applied to a tiling strategy, was
then applied at a different scale to a site strategy. Desired circulation defined the location for the pinch points, and the tension was
varied across the site to allow for larger wetland cells in the south
where the land is low lying and a culvert would be daylit.
On the next page, a series of flooding shows that the deeper pools
hold water longer.
66

67

68

69

70

Once the surface was generated,
contour lines were cut to demonstrate the complexity and relative
depths of the wetland.

the consequential environmental impacts but
also to transform monofunctional infrastructure

Project Background

into multifunctional community watersheds. In-

Arid cities in the western United States are facing

tegrating ecological performance into the fabric

an imminent cultural, political, and ecological

of a neighborhood is critical to redefining urban

challenge: dwindling sources of freshwater and a

water infrastructure in relationship to everyday

warming climate coupled with rapid population

experience, and questioning the divide between

growth. How can we re-imagine and redesign

nature and culture.

water infrastructure so that monofunctional

The surface I am proposing supports this larger

systems are transformed into resilient socio-eco-

body of work in that I am exploring ways of

logical cycles that engage and expand everyday

constructing the ground that provide for the

experience, promote alternative cultural prac-

programmatic and performative requirements of

tices, and reveal latent ecological processes?

a prototypical site: a residential street. Perfor-

This project proposes prototypical interventions

mative requirements include distributing and

that reconfigure stormwater and greywater infra-

cleaning stormwater and greywater, as well as

structure to initiate layered social and ecological

storing the cleaned water for re-use or allowing it

structures in a typical Los Angeles neighbor-

to infiltrate the local aquifer.

hood. Prototypes are proposed at multiple

73

Figure 1
Artificial watershed of Los Angeles
74

Figure 2
Los Angeles water cycle
75

Figure 3
Los Angeles Aquifers Section

Figure 4
Proposed Street Section

76

Figure 5
CA Habitats

Figure 6
Layered Social and Ecological Performance

77

Subvert linearity | facets

Embrace linearity
Shift program

SLEEPING
HOUSES

Subvert linearity | meander

Subvert linearity | cross direction

Embrace linearity| subvert public
private | shift program

Subvert linearity | patchwork

Subvert linearity | continuous surface
with perforations

BATHHOUSES

?

Figure 7
Exploring block typologies

78

Figure 8
Patchwork Plan

I considered various methods of changing the spatial organization of a residential street to
alter the typical linear monofunctional divisions that separate vehicles, pedestrians, water
and vegetation into road, sidewalk, gutter and front lawn.

After exploring many ways of transforming the organization and correlated performance of a street I settled on the patchwork diagram as a prototype to explore in
more depth. Intermixing surfaces for greywater treatment, stormwater collection,
gathering and circulation provides a high degree of complexity and diversity within a
relatively simple framework.
79

gradients from wet to dry and warm to cool as
well as material choices, constructed and planted

Paver type 3 also can be filled with sand & gravel
to form microbasins across a slope for cleaning
greywater. Greywater expelled from residences
or businesses will fill initial larger basins that can
handle surges of water and then flow slowly from
one microbasin to the next. Because greywater

Pollockâ&#x20AC;&#x2122;s
Branch
watershed
has becomed
a hybridized
infrastructure
composed
of pipes and
creeks which
drains much
of south downtown. Because
of urbanization, the watershed cannot
return to its
predevelopment state. We
must rethink
our approach
and employ
a full range of
strategies from
infiltration
ponds high in
the watershed
to stabilization
and filtration
lower.

98

Friendship
Court turns
its back on
Garrett Street,
leaving a nomanâ&#x20AC;&#x2122;s land in
between the
two.

Impervious
surfaces direct
stormwater
into storm
drains that
empty directly
into Pollockâ&#x20AC;&#x2122;s
Branch. This
results in a
polluted and
eroded stream
channel. Adding more pervious surfaces
and areas that
slow, hold,
and infiltrate
water will help
alleviate these
issues.

99

There exists
a vast range
of paving
experiments
which provide
precedent
for creating
a gradient of
infiltration,
retention and
conveyance.

Figure 1

Figure 4

Figure 2

Figure 3
100

Figure 5

Figure 6

Figure 7

Figure 8
101

Right: Small
paver models
were quickly
cut in the
wood shop
with basic
tools. Different
arrangements
of these pieces
create different networks
of water
movement,
retention, or
infiltration.
Opposite: Half
scale wood
models were
made to get a
sense of scale
for the rills and
cuts.

102

Altering mesh
surfaces in
Rhino, we were
able to subtly
manipulate
the surfaces
and use the
router to
produce more
subtle surfaces
for conveying,
storing and
infiltrating
water than the
woodshopâ&#x20AC;&#x2122;s
tools were
suited for.
Center:
Rhinocerous
screen captures of paver
models.
Bottom:
Routing a
positive, full
scale, mock-up
of a retention
paving tile.
103

BASIC

TRANSITION

12”
36”
INFILTRATE
2”

FILTER

CONVEY

104

SLOPED

SECTION

2”
2”

.25”

105

1.5”

This proposal
for the threshold between
Garrett Street
and a new
mixed income
housing neighborhood uses
grading to
provide extra
infiltration
capacity in a
highly urbanized part of
the watershed.
“Infiltration
bosques” use
planted form
to help define
infiltration areas along with
the differentiation of pavers
at the edge.

Above:
Perspective
showing
graded earth
with pavers
overlaid.
Below: A
concept for
a cistern
bench which
integrates a
hand pump to
activate water
rills in tiles
with rainwater
from the buried cistern.

107

This proposal for the threshold
between the IX Complex and the
Pollockâ&#x20AC;&#x2122;s Branch riparian corridor
uses a variety of techniques to
hold, filter, and store water while
also providing new public spaces
for people to inhabit.

PICNIC PAUSE

Plans for three scenarios that
convey, hold, and infiltrate water.
Top: Infiltration pavers allow water to seep into ground. Grass is
able to grow through the pavers,
providing a soft place to sit.
Middle: The active alcove is made
up of smooth pavers that shed
water to the edges where water is
hed and filtered by plants.

ACTIVE ALCOVE

Bottom: In the habitat haven,
puddle pavers hold water and
provide bathing and drinking
water for birds and other urban
critters.

RED RAMP TO A NEW NORMAL
GREEN INFRASTRUCTURE AS PUBLIC SPACE
Rachel Vassar

flows
porosity
accessibility

This exploration builds on my studio work from

spaces must now take on the added charge of

Studio 7010, “Green Infrastructure as Public

improving the ecological functioning of cities.

Space,” undertaken in the Fall of 2012 with Leena

The red paver cladding the ramp that forms the

Cho and Beth Meyer. My design, “Red Ramp to

spine of Charlottesville’s City Market district is

a New Normal”, decenters the paradigm of full

more than a wayfinding devise situating the mar-

ambulatory functioning with a multi-block urban

ket district as a public space with connections to

ramp, positioning the spatial experience of the

Charlottesville’s Downtown Mall. Layered onto

elderly and wheelchair bound as the central

the social agenda of both associating and dif-

model.

ferentiating the Market and the Mall, the ramp’s
paving treatment contains the ecological pro-

The proposal also recognizes that there is no

gram of addressing Charlottesville’s stormwater

one size fits all solution to creating vibrant public

management needs. A porosity gradient within

space that suits the needs of a diverse urban

the language of the Market District’s paving

population. Picking up on dramatic topographic

distributes urban stormwater away from certain

fluctuations on site, an emphasis is placed on

areas and collects it in others. At the same time,

the groundplane as a vehicle for introducing a

these differences in paving reinforce the social

multiplicity of spatial conditions. This variety is

goals of the project, creating areas of optimal

achieved through the use a single “brick-like”

circulation for users of varying physical abilities,

paving unit with differntiated sides that morph

and encouraging gathering and moments of

planemetrically and sectionally, creating a

pause in areas where the rapid movement of

thickened surface onto which increased socio-

people is less ideal.

ecological functioning is projected.

Background
In addition to the ever-elusive task of placemaking, newly designed and redesigned urban public
111

Process
The paving system in this project relies on two
gradients - one of storage and infiltration of water,
and one of speed of pedestrian movement. There
is an inverse relationship between the the two.
Where the paving allows for the most water storage and infiltration, pedestrian movement slows
to a stop; where the pavers are the least permeable, and incapable of water detention, people
can circulated with the greatest ease and speed.

The Unit
These distinctions are achieved through four
methods of differentiation: The presence/absence of micro-basins on the face of the paver,
and the size of the micro-basins when they are
present; the overall verticle profile of the paver
side; the overall horizontal profile of the paver
side; and the arrange of the pavers as a group.

Figure 1
Diagram exploring the speed and direction of human movement, the
direction of water sheeting, and the rate of water absorbtion where
infiltration occurs.

Figure 2
Concept diagram illustrating
inverse relationship between
the flow of water and the flow of
people through different paving
conditions on the site.
112

Figure 3
Four speeds of human circulation - rapid directed movement, strolling, pausing, and
stopping - correlate with four types of paving conditions, each of which forms a portion of
the site. These paving conditions each have different water detention capacities, some
facilitating significant storage, while others are completely unabsorbant. In addition to the
four paving options, a fifth groundplane condition exists, where urban water infilitration
is prioritized over the movement of people. In these areas there is no paving, and human
occupation is not permitted.
In relation to the projectâ&#x20AC;&#x2122;s farmerâ&#x20AC;&#x2122;s market program, strolling is connected to browsing and
pausing to buying.
113

Belle Isle
This landscape, located just south of the VCU campus, provides the
inspiration for this project. It is incredibly lively and full of people
on a spring day during a site visit. It exists as a successful landscape
program, which is why I intend to re-construct it. This project will
first adapt the language of this site into a gridded and highly controlled system before exploring more â&#x20AC;&#x153;naturalâ&#x20AC;? forms.

122

Figure 3
Children
playing on
the rocky
landscape

Figure 4
VCU students
and Richmond
locals enjoying their day
off

Figure 5
Void
conditions

123

Figure 6
Working in
Grasshopper

Figure 7
Developing
pathways

Figure 8
Planting

Figure 9

gradient

Prototype renderings

124

Figure 10
CNC Onsrud
here at
University of
Virginia
School of
Architecture

Figure 11-13
Protoypes in
full scale, half
scale, and
quarter scale

125

Figure 14

Pathway module

Field
conditions

Foothold module
Planting program

Extrude/seated form

â&#x20AC;&#x153;Webâ&#x20AC;? series

Figure 15
Field gradient
of water,
pathways,
and nature in
reference to
the Rivanna
River bank
*see next
page

Figure 17
Concept
applied to
Rivanna River
in Charlottesville. Virginia

127

Figure 18
Belle Isle
inspired form,
referred to as
a “web”

Figure 19
Mastercam
tool paths

Figure 20
Foam mold
produced by
CNC Router
(4’ x 8’)

128

Figure 21
Concrete
casted in to
mold

Figure 22
Concrete pavers removed
from mold
after curing
over night

Figure 23
Initial
configuration

129

Figure 24
Site
installation
(Fine Arts
Grounds)

Figure 25
Detail of
inner â&#x20AC;&#x153;webâ&#x20AC;?

130

Figure 26-27
Bounding the “web” in to 5’ x 5’ box creates a tile-like system that will allow these installations to sit
more seamlessly next to one another. This will allow the framework to expand more easily over time
because its edge conditions are not as particular as the original “web” form.
131

CULVERT, SEDIMENT, RIVER
OCCUPATION
daylighting
hydrology

URBAN RIVER GARDEN
Sarah Schramm

circulation
fractal
islands
channels
filtration

An urban river garden creates a space of gather-

filters toxins, nutrients, and sediments out of the

ing, exploration, movement, pause, and vegeta-

water, and creates habitat for riparian species.

tion along an urban river. No longer considered
scrap land for being undevelopable and a hassle

Project Background

to cross, the urban river garden gives the water a

Inspired by the form of Islamic water gardens of

place in the city and makes it more accessible for

four water channels leading to a central pool,

enjoyment.

and the accessibility of the water to those in the
garden, I created a sloped, gridded surface with

Introduction

orthogonal channels. The slope of those chan-

In examining the spatial relationship between

nels direct water throughout the garden allowing

people in Baltimore and Jones Falls, it becomes

water flows to join and separate. This indirect

clear that there are two drivers of separation

path of the water slows the velocity allowing

between them. The first driver is contamina-

sediments to drop out, creates extensive surface

tion. For aesthetic and health reasons, people

area for filtration, expands the space available

do not want to be near water that has toxins or

for periodic high volumes of water. Furthermore,

pathogens in it, and this impulse has reduced

the grid pattern mirrors that of the gridded city,

the interaction between people and the river

connecting the flow of traffic to the flow of water

over time. The second driver, partially stem-

and the islands in between to city blocks.

ming from the first issue of contamination, is
constructed barriers. Retaining walls, flood walls,
high bridges, and an expressway converting the
channelized Jones Falls into a culvert all make
it difficult for people to access or even view the
river. This project proposes a strategy of creating
an occupiable surface that alleviates flooding,
133

through sand; and geosynthetic polymers that
bind sand together. Polymer and biological sand

Introduction

binders are particularly intriguing because they

Barrier islands are always on the move, respond-

apply fewer outside materials and provide the

ing to changes in nearshore sediment fluxes and

possibility of reapplication of a road surface on

changes in sea level. On the east coast of the

top of overwash sand.

United States, many developed barrier islands
were actively moving shoreward prior to being

Polymer Binders

pinned in place by development. Sand-covered

This project began with an exploration of

asphalt roads and paths are a perennial problem

biodegradable polymers or biological binding

on these islands, typically managed (with varying

agents to bind existing sand into a migratory

degrees of success) with street sweeping. This

road surface (essentially an â&#x20AC;&#x153;unpavedâ&#x20AC;? sand

project asks--how can road and path construc-

road). This surface could be reapplied on top

tion respond directly with this precondition of

of a geofiber bound sand base in response to

the site?

the gradual accumulation of sand layers. This
surface could be patterned and compacted using

Precedents

a custom-tooled compacting cylinder, and the

Many of the most ingenious approaches to build-

pattern pressed into the sand will ideally provide

151

some self-cleaning ability that responds to shifting coastal winds,
allows access by bikes and light vehicles, and accomodates the
infiltration of rainwater into underlying sand substrates (a pervious
paving strategy). In order to meets these objectives, several pattern
types were explored, beginning with the language and processes of
ripple formation in beach sands.
Ripples form from interaction of winds with sand surfaces. Basic
ripple formation starts with a discontinuity in the sand surface. On
the downwind side of a concave depression in the sand, the combination of saltation by sand grains and more exposure to oncoming
winds tend to move sand quickly upslope, forming a small berm
at the top of the concave depression. On the upwind side of the
depression, sand slips down the face of the concave depression at
a slower rate. The imbalance in this sediment budget favors ripples
growing taller and depressions growing deeper, up to a typical maximum height for ripples, at which the ripples tend migrate laterally
but no longer gain in elevation.

Irrigation and geogrid
Despite the benefits of sand binders as a temporary road-buildling
surface, this project ultimately pursued another, less invasive
technique for establishing overwash roads--using a geogrid base
and simple wetting of the surface sand to immobilize and compact
the top layers of sand.
In this system, a stabilized surface is marked with sprinkler buoys
that can wet the sand on dry days, creating visual contrast and
keeping sand from blowing off of the road. Over time, the action of
this applied water along with rainstorms and the wear of drivers on
roads will slowly compact the road into a hard, smooth surface for
driving. The irrigation buoys will provide side benefits for cooling
down sand and beachgoers between the beach and cottages in the
backshore.
In a system of engineered retreat, the overwash road could migrate
landward, replacing infrastructure as it moves.
152

153

1. accumulate

2. bind+ compact

3. accumulate

4. repeat

154

155

CUSTOM
COMPACTING
CYLINDER

Heavy Minerals + Binder

Sand+Binder

Compacted Sand

Pattern 1

1 cm
10 cm

Heavy Minerals + Binder

Heavy Minerals + Binder

Sand+Binder

Sand+Binder

Compacted Sand

Compacted Sand

Pattern 2

Pattern 3
156

157

EPHEMERAL PATHS, ADAPTIVE
MAINTENANCE
circulation
patterns

STUDIES IN RESPONSIVE PATH CONSTRUCTION
John Trevor

blending
interstitial
space
responsive
desire lines

Reconsidering Maintenance
By supplementing traditional path typologies
with informal, temporary walking surfaces, this
project proposes an adaptive path network with
a tighter fit between traffic and structure. Based
on observations of path use on the University of
Virginia central grounds, the new system defines
a path as a concentration of pedestrian flows
within a gradient field of occupation rather than
as a rigid vector with discrete edges. Thus paths
become mobile and responsive to changing
patterns of use. Existing maintenance problems
caused by the movement of people outside path
boundaries are used as inspiration for the proper
form and character of paths.

159

Adaptive Networks
The context for this project is a subject that is
often mundane, but undeniably influential. In
all developed areas from cities to suburbs there
are networks of paths for pedestrian circulation.
While existing networks include paths of various
sizes and materials, almost all are designed to be
permanent, low-maintenance surfaces. Building codes, the generative script for these paths,
dictate minimum dimensions and accessibility
standards. These codes and economic pressure
yield uniform paths that require significant work
to install and are typically impervious. Conventional paths are designed according to general
standards and once built are not easily adapted
to local needs. In this context there are many
opportunities for paths with a short lifespan that
can be easily installed. Formal diversity also provides social benefits, creating informal, dynamic
alternatives to traditional paths with integrated
spaces for lingering, socializing, and other
activities. Focusing on small scale variations in
paths contrasts with the macro-scale concerns
of infrastructural urbanism, yet the investigation
is inspired by the call of Stan Allen and others for
highly responsive networks that can serve many
needs simultaneously.

160

161

0”
6’6”

7’-6”

9’-0”

6”

PAVING ORIENTATION

9”

7’2’-0”
1’-0”

3’-0”
1’-0”
MODERATE WEAR - PATCHY GRASS

9”

’ 7’

2’ 3

HEAVY WEAR - NO GRASS

’

4-5
12” 6” 7’-6” 6” 12”

6”
12”
4’2”

162

Unintended Successes
Worn dirt tracks and eroded path edges already

carrâ&#x20AC;&#x2122;s hill

show the adaptation of existing pathways as foot

fraternity row

traffic blends what was designed as a hard line
into a diffuse gradient zone. The site chosen for
the development of this project is a lawn to the
north of the Rotunda at the University of Virginia.
the corner

The area is crossed by two major brick pathways
with the areas between planted in grass with a

alderman library

mix of mature tree species. These paths are the
primary connections between the residential and

rotunda

academic buildings on Rugby Road, the central
Grounds, Alderman Library, and restaurants on
the Corner.

163

164

165

Dynamic Potential
Due to the high volume of traffic along them they
are three feet wider than typical sidewalks, but
are still unable to accommodate all the demand.
Pedestrians account for most of the traffic, but
cyclists and maintenance vehicles also use them
and are often forced off the path to pass. The
overflow has trampled the grass and compacted
the turf at the edges of the paths into a muddy
border, far from the immaculate edge between
grass and brick desired by the University groundskeepers. At the intersection of paths, the problem
is exacerbated by individuals cutting across the
corner. The tendency of people approaching
an intersection or sharp turn is to create a more
direct route, inscribing a curved desire line inside
the corner. The existing paths acknowledge this
pattern with radiused corners and widened intersections, but these subtle modifications are more
aesthetic than functional. There are also active
strategies in use to prevent wear at corners. A preventative approach is to line the edges of paths
with a temporary rope border, usually done when
new sod is laid. In cases of heavy traffic from
maintenance vehicles, protective turf mats are
used to stabilize the ground, with mixed results.

166

167

GRADIENT

The High Line
New York
James Corner Field Operations

Eerie Street Plaza
Milwaukee
Stoss LU

NEO Bankside
London
Gillespie
168

C.L. EXTG PATH

Responsive Gradients
Desire lines are a challenge to landscape maintenance across the University campus. Though
groundskeepers and administrators see them
as a nuisance and a blemish to be covered over
and prevented, desire lines testify to the range
of movement and activity that path networks

PLAN 1

should accommodate. Implementing a more
diverse range of paths with varying dimensions,
materials, porosity, and permanence is a solution
to the perceived problem that can improve the

3”

overall quality of landscapes. Gradients between
paved surfaces and planted areas have been

SECTION 1

used successfully in recent projects. In the High
BORDER ON FORMAL PATHWAY

Line, James Corner Field Operations designed a

INFORMAL SPUR FROM FORM

small set of paver variations that create a gradient
from fully paved to full vegetation. Stoss LandC.L. EXTG PATH

scape Urbanism used a single rectangular paver

C.L. EXTG PATH

for the Erie Street Plaza, but allowed the pattern
to spread and dissolve where less paving was
needed. These precedents are visually compelling and successfully create informal hybridized
spaces without traditional separations between
programmatic functions. However, they are also
permanent and difficult to adapt to changing

PLAN 2

PLAN 1

P

patterns of use. Though their diffuse form seems
to accommodate variable, shifting use, they are in
reality static.
3”

3”

SECTION 1

SECTION 2

BORDER ON FORMAL PATHWAY

INFORMAL SPUR FROM FORMAL PATHWAY

169

SEC

NEW INFORMAL PAT

Site Manipulations
The challenge of a site with an established
network of paths and a tightly controlled material
palette is distinct from the largely blank slate
presented to the designers of most projects that
have implemented gradient paving. By removing
the option to clear the site and instead making
small study interventions it is possible to observe
how a surface effects changes in pedestrian
movement and is in turn affected by it. As a
model for experimentation, each successive intervention is an opportunity to respond to actual
use. To create a dynamic surface that registers the
movement of traffic across it, layers of crushed
stone are arranged alongside the existing brick
paths following the arcs already worn into the
turf. The loose aggregate is colored to make its
movement easily visible. To create a positive
relationship between traffic moving across the
surface and vegetation, the gravel bed is seeded
with plant species that can grow under different
levels of foot traffic. Instead of the single grass
type found across the lawns, the new species and
pedestrians will create a fluctuating pattern of
grasses.

Site Studies
Grid, Offset, Fillet
170

LAYERING

Desire Line Arcs
Added Program

Tree Canopy

Path Demand

8â&#x20AC;&#x2122; Base Grid

171

Programmatic Diversity
To encourage a wider range of activity on the site
the new surface includes subtle lines of brick and
gravel leading to spaces in the lawns defined by
plantings of another grass species. These small
trails signal that the lawns are intended to be
used not just passed by. The border added to the
existing path swells to create small pockets where
passing friends can stop to catch up and visiting
families can stop to decide where to go next. In
the triangular island between three paths the
surface creates a new zone for lingering, talking,
and watching at this busy intersection.

4-Inch Grid

4-Foot Grid

Existing Paving

172

173

Seasonal Change
In addition to the functional benefit of turf stabilization and the circulation benefit of greater path
options, this surface can be a means of registering seasonal changes and marking major events
in the university community. The colored layers
of crushed stone in the surface complement the
seasonal patterns of vegetation through the year.
Additional applications of crushed stone in the
Universityâ&#x20AC;&#x2122;s colors (Blue Pantone 294 and Orange

Marking major public events.

Pantone 145) would be made for specific important events such as the start of classes, Final
Exercises, football games, and Alumni Weekends.
The changing colors would be a visible reminder
of the range of activities going on throughout the
academic year.

174

Calendar Year

UVA Academic Year

August

24-26 Orientation

September

27 Fall Courses Begin

October

27-29 Family Weekend

November

27-1 Thanksgiving Recess

December

6 Fall Courses End

Other Events

Football Season

Winter Storms
January

2-10 January Term

February

13 Spring Courses Begin

March

20 MLK Day

April

8-16 Spring Recess

May

29 Spring Courses End

June

18 Final Exercises

July

Summer Courses

Jeffersonâ&#x20AC;&#x2122;s Birthday

Foxfield Races

Independence Day

175

MAINTENANCE, MOWING, TOOLPATH
patterning
succession
(re)vegetation

EDITING EMERGENCE
SURFACE OF LAYERED MAINTENANCE
Michael Geffel

weeds
moiré
suburb
yard
vague terrain
field

Especially following the economic decline of

topography of the lawn or field is also perhaps

the post-war suburb, vast areas of the U.S. are

the clearest expression of the thickness of land-

now shaped primarily through their landscape

scape surfaces. Vegetation is not only closely

maintenance. Understanding (re)vegetation

associated with the geological layers below, but

as an inevitable component of the forgotten

also provides a thickness of its own. Mowing, in

landscape surface, Editing Emergence utilizes

short, can be understood as the operation which

various mowing operations to edit plant

maintains vegetation as a surface and not a wall

succession, balancing the tension between care

or other enclosure. As such, it functions as an

and neglect, cleanliness and biodiversity. Two

infrastructural service to prevent vacant lots and

main strategies are identified: the spatial volume

other vague terrain from getting “overgrown.”

and the field pattern. In the first, mowing only

This type of mowing is usually complaint driven

takes place in those areas most under threat

and occurs about twice a year (if at all), in the late

from woody invasion, with the added value of

spring and late summer. As post-industrial cities

creating a spatial volume in what would have

shrink and post-war suburbs reach their shelf life,

been “vacant space.” Patterns are developed by

the mowing burden reaches increases with every

overlaying conventional mow paths to create a

decrease in resources. The ecological benefits

cumulative moiré affect. Both are used to guide

gained from this spontaneous revegetation are

visual and physical access through a site, reduce

usually overlooked, and instead are perceived

overall mowing, and give an aesthetic signature

negatively as a sign of blight, of neglect. In this

to vague terrain.

proposal, coexistence hybridizes unplanned
revegetation with the care of maintenance to

Introduction
Mowing is perhaps the closest connection to the
landscape surface that an American has, with the
explicit goal of reducing the height of vegetation
and recreating an occupiable space. The micro177

Project Description
Like all maintenance, economy of operations
is paramount to mowing and if any alternative
strategy is to be received favorably it must reduce
overall mowing. One way to achieve this is by adhering to convention so that the design remains
legible to operators and achievable in the field.
By diagramming “the rules” of conventional mow
paths, aesthetically and spatially desirable opportunities were identified for the shrinking city.
Two main strategies are identified: the spatial
volume, and the field pattern. In the first, mowing
only takes place in those areas most under threat
from woody invasion, with the added value of
creating a spatial volume in what would have
been “vacant space.” Patterns are developed by
overlaying conventional mow paths to create a
cumulative moiré affect. Both are used to guide
visual and physical access through a site, reduce
overall mowing, and give an aesthetic signature
to vague terrain. Both are also intended to
be performed at the beginning of the mowing
season in late Spring. For the late Summer
mowing, the previous paths can be repeated to
create frames around successional vegetation or
the entire site can be mowed for a blank slate the
following year.
In total, eight operations were designed, and
range in complexity and time savings. Each were
originally drawn in plan based on the formal
logic of the mowing typology and then drawn in
axon to better communicate their spatial affects.
178

Figures 1-4
(left)
Gilles Clement
is known as a
pioneer of â&#x20AC;&#x153;design through
gardening,â&#x20AC;?
but the spatial
potential of
maintenance
can also be
found in the
art world
(Dennis Oppenheim) and
throughout
the vernacular
landscape.

“Mow headrows along edge, then mow
perpendicular to street every X feet to create
unmowed boxes.”
78% of conventional mow time

big box

“Zamboni along irregular edge perpendicular
to street, then Zamboni straight rows parallel to
street.”
93% of conventional mow time

field moiré

Figure 10
As the
operator
becomes
more familiar
with these
sequences,
more complex
patterns may
be established.

“Start by mowing a spiral. After it becomes a zamboni,
mow one headrow. Pick a direction and mow across
the field, turning 90° towards the most open side
every time you reach the edge until satisfied.”
61% of conventional mow time

roomba

182

183

Figure 12

Figure 11

Figure 13

Figure 14

Figure 15

Figure 17

Figure 16

Figure 18

Figure 19
184

Patterns were also explored parametrically to be able to quickly represent the scalar
differences of various mowing instruments. All designs were modelled using CNC and
then finally tested with a walk-behind, rotary lawn mower to understand feasibility
and material response at the body scale.

to be harvested until it is needed, significantly
reducing refrigeration loads. A challenge to

As a unit intended to be a tileable module,

widespread implementation of this model is the

the geometry of the units could be adjusted

popular belief in much of North America that

based on the specific climatic conditions of the

thriving vegetable gardens are a seasonal oc-

intended installation site. In addition, the mate-

currance. While there is a seasonal cycle to the

rials would ideally be as light as possible to limit

growth of edible plants, by staggering planting

the addtional structure necessary to support

and protecting plants from wind and frost, fresh,

such a roof garden. Other functions that could

diverse foods can be harvested year-round.

be incorporated into the unit are water proofing,

1

and irrigation.
187

In practice, this unit would serve the role of
the “eggcrate” layer in conventional green-roof
assemblies (Fig. 5). Rigid, relatively light-weight
plastic is the most common material for this
layer, and is similarly a reasonable material for
these units, satisfying the requirements for weigh,

Figure 1

waterproofing, and strength.
In order to provide increased wind protection,
the traditional straight wall of the sloped-bed
system could be curved or angled (Fig. 2). To
take advantage of the radiant energy of the low
winter sun, the “wall” portion of the assembly
could be backed on the south slope with a highthermal-mass material, such as masonry, or even
water. The geometrical relationship between
the height of the “wall” and the winter angle of
the sun would govern the width of the walkway,
with a minimum width of about 24” for ease of
maintenance and harvest (Fig. 3). An alternative parameter for controlling the height of the
hillocks is to base their heights on their distance
from a specific point, with more tender crops
planted in the more protected pockets.

Figure 2

Like traditional terra-cotta roof tiles, these units
would overlap and interlock to cover the roof
area. Channels within each unit would store gray
water that fell on the garden, but could also be
used for irrigation. Gutters at the sides of the
units would act as an overflow failsafe for the
irrigation channels, and could channel surplus
water to a graywater storage system to feed the
occasional irrigation needs.
Figure 3
188

object which comes in contact with the body.
To test my hypothesis, I constructed a one-third
scale model to take temperature readings. The

Introduction
The project was conceived as part of a study in

mold was constructed using CNC fabrication and

thermal dynamics in the landscape, and applied

poured with high-performance ductal concrete.

to public space within a farmers market. The

The bench began to preform immediately, as

bench uses the principle of thermal mass and

the endothermic reaction of the curing concrete

lagging temperatures to create varied conditions.

created perceptible thermal gradients. At the

It was created through the use of concrete and

completion of the curing process, the bench was

metal aggregates, which were then placed in a

placed outside and it continued to register gra-

dynamic environment.

dients upwards of ten degrees from end to end,
responding to the diurnal fluctuations.

Project Background
My hypothesis stated that by forming one end of
the bench with a larger thermal mass than the
other, that endâ&#x20AC;&#x2122;s temperature would lag when
shifting from cold to hot, staying colder longer or
vice versa. The bench form was created beginning with a solid mass, then subtracting material
away to create a gradient of voided space. Metal
aggregates were added into the concrete mix in
order to increase the thermal coefficient of the
195

The bench was conceived as an addition to a
system created for a larger field of thermal gradients, including pavers, vegetated surfaces, and
canopies as a means of organization. The surface
and canopies create comfortable outdoor
spaces; extending the seasons and stretching the
comfort of one season into the next.

196

internal temp
high mass

low mass

morning

afternoon

ambient temp

evening

This intervention does not reinforce a homogenous condition or static character. It seeks
to increase awareness and understanding of
change and specific properties of material, light,
and movement. Space is conceived through its
properties and its seasonal and diurnal change;
itâ&#x20AC;&#x2122;s perceived and experienced as relational,
contingent and fluctuating.